DHCP lease renewal fails

[pgr]

Hi,

I had Win2000 computer running Wingate 6.0.4 smoothly, connecting through a cable modem to my ISP.

A few weeks ago, without changing anything in my server (though perhaps some Windows Updates took place), I started having periodic Internet access problems. After some investigation, I found that the DHCP lease (which are re-assigned every 30 minutes by the ISP) was failing renewal. When the lease expires, I lose the IP address for a couple of minutes, then it comes back and I have Internet access for another half an hour.

All this goes on and off without touching anything, without having to reset the modem, restart WinGate, nothing.

I thought this was a problem with the ISP's DHCP server, but I called them and they said they weren't experiencing any problems. I tried connecting my portable PC directly to the cable modem and it worked great, with no loss of connection (DHCP lease renewed with no problems).

So, that means it's something with the Wingate PC (even though it might be a problem with the OS, not with Wingate software).

Can anybody help? Is there anything I can do to further diagnose the DHCP problem?

Thanks in advance!
Pedro

[jamesc]

1. What is the brand name and model of your modem?
2. Is it Internal / External


a) Do you see any firewall hits on port 67
b) Does your modem get a public IP address.
c) Which windows updates have you installed since this prob has arisen?
d) (excuse this question) Is your computer protected against viruses / spyware?

Hopefully with the above details we can try and help you work this out.

Sidenote: Reassigned every 30 mins? wow.

[pgr]

Thanks for your post.

I'll try to answer your questions... but I don't specialise in this sort of stuff, so forgive me if my answers are not so good...

1) The modem reads "ELSA Microlink Cable". It's external. It's been there working fine for years.

a)I'm not sure about your firewall question, we don't use a firewall except for Wingate, which does the firewall work, as far as I know. I don't see anything in Wingate regarding port 67.
b) I'm not sure what this means. The Ethernet network adapter that connects to this modem gets a public IP address. It is our bridge to the outer world, and it the one that's suffering from this DHCP assignment problem.
c) 16th April - Cumulative Security Update for Internet Explorer 5.01 for Windows 2000 SP3 (KB890923)
16th April - Security Update for Windows 2000 (KB893066)
16th April - Security Update for Windows Server 2003 (KB890859)
16th April - Security Update for Windows XP (KB893086)
16th April - Windows Installer 3.1 Redistributable (KB893803)
16th April - Update for Background Intelligent Transfer Service (BITS) 2.0 and WinHTTP 5.1 Windows Server 2003 (KB842773)
17th May - Security Update for Windows 2000 (KB894320)
22nd May - Windows Installer 3.1 (v2) [kb893803]

I tried unistalling KB842773 (BITS/WinHTTP), since it seemed to be related to the network, but the DHCP problem persisted.

I believe our problem started somewhere around the begginning of May, but I admit it might be around since those 16th April updates. At first we didn't realise the connectivity problems were regular, it took us a few weeks to build up a strange feeling that the "Internet was failing more often than usual".

d) We don't use additional antivirus/spyware protection. Wingate blocks some attacks, and Windows Updates should keep us reasonably protected. Nobody sits at that PC or works on it, so the risk of opening malicious mail attachments is not present. Of course, I know this isn't ideal security, but it's been sufficient so far. Anyway, I'm used to looking at the Task Manager process list (and the several way to auto-run processes when the PC starts) and I think I can tell when a computer has something suspicious going on. I don't think that is the case.

Thank you for your help, I hope this information is useful...
Pedro

[pgr]

BUMP!

can I get some more help please... the problem is still happening...

[jamesc]

Hi,

KB893066 has been known to create some problems with WinGate. Can you uninstall it and see if you are still having these problems?

[pgr]

Thank you, I've uninstalled it.

I'll try to see if the problem continues or not, then I'll come back and let you know.

Thanks

[pgr]

I'm afraid everything is still the same: uninstalling the update did not solve the problem.

Do you have any further suggestions?

Thank you for your patience and help.
Pedro

[pgr]

BUMP!

Can I get some help please?

[jamesc]

Can you please submit a support request here: http://support.qbik.com/index.php?_a=tickets&_m=submit ... And add the following information.

1. While connected to the internet on your WinGate computer, please find out its IP address setings. (Windows) Start Menu --> Run --> CMD --> ipconfig /all >> C:\ipa.txt
This will create a text file with your ip address settings. Its location will be C:\ipa.txt

2. Can you also attach a configuration report of WinGate. (Windows) Start Menu --> Programs --> WinGate --> GateKeeper --> Options Menu --> Advanced --> Save Report button

[jamesc]

I have discussed this with a colleague. The files you sent seem in order. Can you do one more test before we get a bit deeper into this problem. Can you install WinGate 6.0.4 on your laptop, activate a trial license, and see if you still get a few minutes of disconnection. We just want to eliminate a possible windows operating system problem.

http://www334.pair.com/qbiknz/downloads ... 25-USE.EXE